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authorGreg Ungerer <gerg@uclinux.org>2011-03-22 13:39:27 +1000
committerGreg Ungerer <gerg@uclinux.org>2011-03-25 14:05:13 +1000
commit66d857b08b8c3ed5c72c361f863cce77d2a978d7 (patch)
tree47222d86f4d78dc0da31baf64188bd2e4b38ac1e /arch/m68k/platform/coldfire/pit.c
parentd39dd11c3e6a7af5c20bfac40594db36cf270f42 (diff)
downloadop-kernel-dev-66d857b08b8c3ed5c72c361f863cce77d2a978d7.zip
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m68k: merge m68k and m68knommu arch directories
There is a lot of common code that could be shared between the m68k and m68knommu arch branches. It makes sense to merge the two branches into a single directory structure so that we can more easily share that common code. This is a brute force merge, based on a script from Stephen King <sfking@fdwdc.com>, which was originally written by Arnd Bergmann <arnd@arndb.de>. > The script was inspired by the script Sam Ravnborg used to merge the > includes from m68knommu. For those files common to both arches but > differing in content, the m68k version of the file is renamed to > <file>_mm.<ext> and the m68knommu version of the file is moved into the > corresponding m68k directory and renamed <file>_no.<ext> and a small > wrapper file <file>.<ext> is used to select between the two version. Files > that are common to both but don't differ are removed from the m68knommu > tree and files and directories that are unique to the m68knommu tree are > moved to the m68k tree. Finally, the arch/m68knommu tree is removed. > > To select between the the versions of the files, the wrapper uses > > #ifdef CONFIG_MMU > #include <file>_mm.<ext> > #else > #include <file>_no.<ext> > #endif On top of this file merge I have done a simplistic merge of m68k and m68knommu Kconfig, which primarily attempts to keep existing options and menus in place. Other than a handful of options being moved it produces identical .config outputs on m68k and m68knommu targets I tested it on. With this in place there is now quite a bit of scope for merge cleanups in future patches. Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Diffstat (limited to 'arch/m68k/platform/coldfire/pit.c')
-rw-r--r--arch/m68k/platform/coldfire/pit.c169
1 files changed, 169 insertions, 0 deletions
diff --git a/arch/m68k/platform/coldfire/pit.c b/arch/m68k/platform/coldfire/pit.c
new file mode 100644
index 0000000..c2b9809
--- /dev/null
+++ b/arch/m68k/platform/coldfire/pit.c
@@ -0,0 +1,169 @@
+/***************************************************************************/
+
+/*
+ * pit.c -- Freescale ColdFire PIT timer. Currently this type of
+ * hardware timer only exists in the Freescale ColdFire
+ * 5270/5271, 5282 and 5208 CPUs. No doubt newer ColdFire
+ * family members will probably use it too.
+ *
+ * Copyright (C) 1999-2008, Greg Ungerer (gerg@snapgear.com)
+ * Copyright (C) 2001-2004, SnapGear Inc. (www.snapgear.com)
+ */
+
+/***************************************************************************/
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/param.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clockchips.h>
+#include <asm/machdep.h>
+#include <asm/io.h>
+#include <asm/coldfire.h>
+#include <asm/mcfpit.h>
+#include <asm/mcfsim.h>
+
+/***************************************************************************/
+
+/*
+ * By default use timer1 as the system clock timer.
+ */
+#define FREQ ((MCF_CLK / 2) / 64)
+#define TA(a) (MCFPIT_BASE1 + (a))
+#define PIT_CYCLES_PER_JIFFY (FREQ / HZ)
+
+static u32 pit_cnt;
+
+/*
+ * Initialize the PIT timer.
+ *
+ * This is also called after resume to bring the PIT into operation again.
+ */
+
+static void init_cf_pit_timer(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+
+ __raw_writew(MCFPIT_PCSR_DISABLE, TA(MCFPIT_PCSR));
+ __raw_writew(PIT_CYCLES_PER_JIFFY, TA(MCFPIT_PMR));
+ __raw_writew(MCFPIT_PCSR_EN | MCFPIT_PCSR_PIE | \
+ MCFPIT_PCSR_OVW | MCFPIT_PCSR_RLD | \
+ MCFPIT_PCSR_CLK64, TA(MCFPIT_PCSR));
+ break;
+
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_UNUSED:
+
+ __raw_writew(MCFPIT_PCSR_DISABLE, TA(MCFPIT_PCSR));
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+
+ __raw_writew(MCFPIT_PCSR_DISABLE, TA(MCFPIT_PCSR));
+ __raw_writew(MCFPIT_PCSR_EN | MCFPIT_PCSR_PIE | \
+ MCFPIT_PCSR_OVW | MCFPIT_PCSR_CLK64, \
+ TA(MCFPIT_PCSR));
+ break;
+
+ case CLOCK_EVT_MODE_RESUME:
+ /* Nothing to do here */
+ break;
+ }
+}
+
+/*
+ * Program the next event in oneshot mode
+ *
+ * Delta is given in PIT ticks
+ */
+static int cf_pit_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ __raw_writew(delta, TA(MCFPIT_PMR));
+ return 0;
+}
+
+struct clock_event_device cf_pit_clockevent = {
+ .name = "pit",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_mode = init_cf_pit_timer,
+ .set_next_event = cf_pit_next_event,
+ .shift = 32,
+ .irq = MCFINT_VECBASE + MCFINT_PIT1,
+};
+
+
+
+/***************************************************************************/
+
+static irqreturn_t pit_tick(int irq, void *dummy)
+{
+ struct clock_event_device *evt = &cf_pit_clockevent;
+ u16 pcsr;
+
+ /* Reset the ColdFire timer */
+ pcsr = __raw_readw(TA(MCFPIT_PCSR));
+ __raw_writew(pcsr | MCFPIT_PCSR_PIF, TA(MCFPIT_PCSR));
+
+ pit_cnt += PIT_CYCLES_PER_JIFFY;
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+}
+
+/***************************************************************************/
+
+static struct irqaction pit_irq = {
+ .name = "timer",
+ .flags = IRQF_DISABLED | IRQF_TIMER,
+ .handler = pit_tick,
+};
+
+/***************************************************************************/
+
+static cycle_t pit_read_clk(struct clocksource *cs)
+{
+ unsigned long flags;
+ u32 cycles;
+ u16 pcntr;
+
+ local_irq_save(flags);
+ pcntr = __raw_readw(TA(MCFPIT_PCNTR));
+ cycles = pit_cnt;
+ local_irq_restore(flags);
+
+ return cycles + PIT_CYCLES_PER_JIFFY - pcntr;
+}
+
+/***************************************************************************/
+
+static struct clocksource pit_clk = {
+ .name = "pit",
+ .rating = 100,
+ .read = pit_read_clk,
+ .shift = 20,
+ .mask = CLOCKSOURCE_MASK(32),
+};
+
+/***************************************************************************/
+
+void hw_timer_init(void)
+{
+ cf_pit_clockevent.cpumask = cpumask_of(smp_processor_id());
+ cf_pit_clockevent.mult = div_sc(FREQ, NSEC_PER_SEC, 32);
+ cf_pit_clockevent.max_delta_ns =
+ clockevent_delta2ns(0xFFFF, &cf_pit_clockevent);
+ cf_pit_clockevent.min_delta_ns =
+ clockevent_delta2ns(0x3f, &cf_pit_clockevent);
+ clockevents_register_device(&cf_pit_clockevent);
+
+ setup_irq(MCFINT_VECBASE + MCFINT_PIT1, &pit_irq);
+
+ pit_clk.mult = clocksource_hz2mult(FREQ, pit_clk.shift);
+ clocksource_register(&pit_clk);
+}
+
+/***************************************************************************/
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